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Empirical Evidence for the Look-Ahead Behavior of Pedestrians in Bi-directional Flows

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Chinese Physics Letters 2012年第6期29卷 299-302页

作者： GUO Ren-Yong WONG SC XIA Yin-Hua HUANG Hai-Jun LAM William H.K. CHOI Keechoo College of Computer Science Inner Mongolia UniversityHohhot 010021 Department of Civil Engineering The University of Hong KongPokfulam RoadHong Kong Department of Mathematics University of Science and Technology of ChinaHefei 230026 School of Economics and Management Beijing University of Aeronautics and AstronauticsBeijing 100191 Department of Civil and Structural Engineering The Hong Kong Polytechnic UniversityHong Kong Department of Transportation Engineering Ajou UniversitySan 5 Woncheon-DongYeongtong-KuSuwon442-749 Korea

Using the sample data obtained from a group of pedestrian experiments,a function formulating the velocitydensity relationship of pedestrians and linear regression is proposed to provide empirical evidence for the lookahead behavior of pedestrians in bi-directional *** find that the velocity of pedestrians is negatively correlated with not only the densities of the opposite-direction and the identical-direction pedestrians around them but also the densities of the same-direction pedestrians ahead of ***,the movement of pedestrians is most affected by other pedestrians moving in the same direction about 1 m ahead.

关键词： directional identical ahead

Depletion of the IKBKAP ortholog in zebrafish leads to hirschsprung disease-like phenotype

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World Journal of Gastroenterology 2015年第7期21卷 2040-2046页

作者： William Wai-Chun Cheng Clara Sze-Man Tang hong-Sheng Gui Man-Ting So Vincent Chi-Hang Lui Paul Kwong-Hang Tam Maria-Mercè Garcia-Barcelo Department of Surgery Li Ka Shing Faculty of Medicine the University of Hong Kong Department of Psychiatry Li Ka Shing Faculty of Medicine the University of Hong Kong Center for Genomic Sciences of the Li Ka Shing Faculty of Medicine the University of Hong Kong Centre for Reproduction Development and Growth Li Ka Shing Faculty of Medicine the University of Hong Kong

AIM:To investigate the role of IKBKAP(inhibitor of kappa light polypeptide gene enhancer in B-cells,kinase complexassociated protein)in the development of enteric nervous system(ENS)and Hirschsprung disease(HSCR).METHODS:In this study,we injected a morpholino that blocked the translation of ikbkap protein to 1-cell stage zebrafish *** phenotype in the ENS was analysed by antibody staining of the pan-neuronal marker Hu C/D followed by enteric neuron *** mean numbers of enteric neurons were compared between the morphant and the *** also studied the expressions of ret and phox2bb,which are involved in ENS development,in the ikbkap morpholino injected embryos by quantitative reverse transcriptase polymerase chain reaction and compared them with the ***:We observed aganglionosis(χ2,P<0.01)and a reduced number of enteric neurons(38.8±9.9 vs50.2±17.3,P<0.05)in the zebrafish embryos injected with ikbkap translation-blocking morpholino(morphant)when compared with the control *** of the morpholino was confirmed by similar results obtained using a second non-overlapping morpholino that blocked the translation of *** further studied the morphant by analysing the expression levels of genes involved in ENS development such as ret,phox2bb and sox10,and found that phox2bb,the ortholog of human PHOX2B,was significantly down-regulated(0.51±0.15 vs 1.00±0,P<0.05).Although we also observed a reduction in theexpression of ret,the difference was not ***:Loss of IKBKAP contributed to HSCR as demonstrated by functional analysis in zebrafish embryos.

关键词： Hirschsprung disease Enteric nervous system IKBKAP

Surface-Assisted Laser Desorption/Ionization Imaging Mass Spectrometry:Noble Metal Nanoparticles as Efficient Substrates for Forensic Applications

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Surface-Assisted Laser Desorption/Ionization Imaging Mass Sp...

中国化学会首届全国质谱分析学术研讨会

作者： Yi-Ching Choi Pui-Yuk Mak Ho-Wai Tang Sin-Heng Man Kwan-Ming Ng Department of Chemistry and State Key Laboratory of Synthetic Chemistry The University of Hong Kong

Chemical analysis of forensic evidence collected from a crime scene is important for criminal *** uniqueness and specificity of chemical information obtained from the forensic sample is critical for successful *** Mass Spectrometry(IMS)is a powerful analytical technique which allows direct chemical analysis of forensic samples without extensive sample *** high sensitivity and specificity,the chemical identity and the spatial distributions of analytes in the sample will be ***,nanomaterials have been used in Surface-Assisted Laser Desorption/Ionization(SALDI)-based MS and IMS as substrate for forensic sample *** have applied Gold Nanoparticles(AuNPs)as efficient LDI substrate in previous *** samples including latent fingerprint and questioned documents were firstly coated with a layer of AuNPs using solvent-free Argon Ion Sputtering,followed by the subsequent spectrometric *** imaging of latent fingerprint can be *** latent fingerprint can be optically visualized due to the plasmonic properties of ***-and endogenous compounds found on latent fingerprint can also be molecularly imaged by *** document such as cheque with suspicious altered writing can be examined through the minimally-destructive ink analysis by *** using different pens can be distinguished by the MS images targeting different characteristic ions with specific m/z ***,altered words can be identified on the questioned *** team is developing other noble metal nanoparticles,such as silver nanoparticles(AgNPs),platinum nanoparticles(PtNPs),palladium nanoparticles(PdNPs)and bimetallic nanoparticles with welldefined physiochemical properties as potential efficient substrates for SALDI-MS and-IMS *** anticipate that the use of nanoparticles as substrate will enhance the analytical performance and extend the application in forensic science.

关键词： Surface-assisted Laser Desoprtion/lonization-Mass Spectrometry Imaging Mass Spectrometry Noble metal nanoparticles Forensic science

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World Journal of Gastroenterology 2008年第28期14卷 4535-4539页

作者： Guo-Shuang Feng Jun-Ling Ma Benjamin CY Wong Lian Zhang Wei-Dong Liu Kai-Feng Pan Lin Shen Xiao-Dong Zhang Jie Li Harry HX Xia Ji-You Li Shiu Kum Lam Wei-Cheng You Department of Cancer Epidemiology Peking University School ofOncology Beijing Cancer Hospital & Institute Beijing 100036 China Department of Medicine University of Hong Kong Hong Kong China Department of Medical Oncology Peking University School of Oncology Beijing Cancer Hospital & Institute Beijing 100036 China Department of Pathology Peking University School of Oncology Beijing Cancer Hospital & Institute Beijing 100036 China Healthy Bureau of Linqu County Weifang 262600 Shandong Province China

AIM: To evaluate the long-term risk of gastroduodenal ulcer and cardiovascular events induced by celecoxib in a population-based, randomized, double-blind, placebo-controlled ***: From 2004 to 2006, a total of 1024 Chinese patients (aged 35 to 64 years) with severe chronic atrophic gastritis, intestinal metaplasia or dysplasia were randomly assigned to receive 200 mg of celecoxib twice daily or placebo in Linqu County (Shandong Province, China), a high-risk area of gastric cancer. All gastroduodenal ulcer and cardiovascular events occurred were recorded and the patients were followed up for 1.5 years after treatment. At the end of the trial, a systematic interview survey about other adverse events was conducted. RESULTS: Gastroduodenal ulcer was detected in 19 of 463 (3.72%) patients who received celecoxib and 17 of 473 (3.31%) patients who received placebo, respectively (odds ratio = 1.13, 95% CI = 0.58-2.19). Cardiovascular (CV) events occurred in 4 patients who received celecoxib and in 5 patients who received placebo, respectively. Compared with those who received placebo, patients who received celecoxib had no signif icant increase in occurrence of CV events (hazard ratio = 0.84, 95% CI = 0.23-3.15). Among the adverse events acquired by interview survey, only the frequency of bloating was signif icantly higher in patients treated with celecoxib than in those treated with placebo. CONCLUSION: Treatment of gastric cancer with celecoxib is not associated with increased risk of gastroduodenal ulcer and cardiovascular events.

关键词： Celecoxib Gastroduodenal ulcer Cardiovascular diseases Adverse effects Epidemiology Randomized controlled trial

On Eigen-Matrix Translation Method for Classification of Biological Data

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Journal of Systems Engineering and Electronics 2015年第5期26卷 1212-1230页

作者： JIANG Hao QIU Yushan CHENG Xiaoqing CHING Waiki Department of Mathematics School of Information Renmin University of China Advanced Modeling and Applied Computing Laboratory Department of Mathematics The University of Hong Kong

Driven by the challenge of integrating large amount of experimental data, classification technique emerges as one of the major and popular tools in computational biology and bioinformatics research. Machine learning methods, especially kernel methods with Support Vector Machines （SVMs） are very popular and effective tools. In the perspective of kernel matrix, a technique namely Eigen- matrix translation has been introduced for protein data classification. The Eigen-matrix translation strategy has a lot of nice properties which deserve more exploration. This paper investigates the major role of Eigen-matrix translation in classification. The authors propose that its importance lies in the dimension reduction of predictor attributes within the data set. This is very important when the dimension of features is huge. The authors show by numerical experiments on real biological data sets that the proposed framework is crucial and effective in improving classification accuracy. This can therefore serve as a novel perspective for future research in dimension reduction problems.

关键词： Classification dimension reduction eigen-matrix translation glycan data kernel method(KM) support vector machine (SVM)

Biomaterial nanotopography-mediated cell responses:experiment and modeling

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International Journal of Smart and Nano Materials 2014年第4期5卷 227-256页

作者： Lei Yang Haipei Liu Yuan Lin Institute of Orthopaedics and Department of Orthopaedic Surgery The First Affiliated HospitalSoochow UniversitySuzhou 215006PR China Department of Mechanical Engineering The University of Hong KongPokfulam RoadHong KongPR China

The rapid development of fabrication and processing technologies in the past two decades has enabled researchers to introduce nanoscale features into materials which,interestingly,have been shown to greatly regulate the behavior and fate of biological *** particular,important cell responses(such as adhesion,proliferation,differentiation,migration,and filopodial growth)have all been correlated with material *** its great potential,intensive efforts have been made,both experimentally and theoretically,to understand why and how cells respond to nanoscale surface features,and this article reviews recent progress in this ***,a brief overview on the fabrication and modification techniques to create nanotopography on different materials is given *** that,a summary of important experimental findings on the mediation of nanoscale surface topography on the behavior of various cells,as well as the underlying mechanism,is ***,both classical and recently developed approaches for modeling nanotopographymediated cell adhesion and filopodial growth are reviewed.

关键词： biomaterials topography cell-material interaction experiment modeling

Botanical C-glucosylated Isoflavone Puerarin Suppresses Nitric Oxide-induced Neurotoxicity Via Inducing Arginase-2 Expression

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Botanical C-glucosylated Isoflavone Puerarin Suppresses Nitr...

A study on population dynamics in“Belt&Road”countries and their implications

第十四届全国中药和天然药物学术研讨会

作者： Jia Zhao Yifan Han Jianhui Rong The university of hong kong

＜正＞Aberrant production of reactive oxygen species（ROS）and reactive nitrogen species（RNS）is implicated in the ageing process and the pathogenesis of neurodegenerative diseases,major depression,schizophrenia and bipolar *** is an antioxidant and neuroprotective C-glycosylated isofiavonone derived from a group of edible plants in the genus of pueraria

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China Population and Development Studies 2018年第2期2卷 158-172页

作者： Mengni Chen Paul S.F.Yip Department of Social Work and Social Administration The University of Hong KongPokfulamHong Kong Wittgenstein Centre(IIASA VID/ÖAWWU)Vienna University of Economics and Business(WU)Welthandelsplatz2Level 21020 ViennaAustria

China’s Belt&Road(“B&R”)initiative has attracted much attention in recent *** studies have assessed the potential impacts of this initiative from the economic,political,foreign relations,and military ***,very little attention has been paid to examine the opportunities and challenges of this new initiative from a demographic ***,this study investigates into the population dynamics of 65 countries in the B&R region,and explores the demographic dynamics of this regional cooperation *** on graphic visualization,the demographic heterogeneities within the B&R region,in terms of current stages of demographic transitions,population age structure,and demographic windows of opportunities have been ***,a model-based cluster analysis has been conducted to classify the B&R countries into two *** group consists of countries with younger population,low education access,and larger gender gap in the labor market,while the other group comprises of more aged population and has better performances in economic development,education enrolment,and female labor *** demographic windows of opportunities in the former group will remain open for the coming decades;whereas the windows have already closed or is about to close very soon in the latter *** former group should take lessons from the latter concerning how to better prepare themselves for the demographic ***,the curvilinear relationship between wealth and well-being has a complicated structure and the B&R initiative should focus not only on economic development but also on the human well-being.

关键词： Belt and road initiative Population dynamics Demographic heterogeneity Economic development Well-being

Three-Di mensional Computations of Multiple TandemJets in Crossflow

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China Ocean Engineering 2006年第1期20卷 99-112页

作者：肖洋李行伟唐洪武 YUDae-Young College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Department of Civil Engineering The University of Hong KongHong Kong China

The mixing and merging characteristics of multiple tandem jets in crossflow are investigated by use of the Computational Fluid Dynamics （CFD） code FI,UENT. The realizable k - ε model is employed for turbulent elosure of the Reynolds-averaged Navier-Stokes equations. Numerical experiments are performed for 1-, 2- and 4-jet groups, tbr jet-tocrossflow velocity ratios of R = 4.2 ～ 16.3. The computed velocity and scalar concentration field are in good agreement with experiments using Particle Image Velocimetry （PIV） and Laser Induced Fluorescence （LIF）, as well as previous work. The results show that the leading jet behavior is similar to a single free jet in crossflow, while all the downstream rear jets have less bent-over jet trajectories - suggesting a reduced ambient velocity for the rear jets. The concentration decay of the leading jet is greater than that of the rear jets. When normalized by appropriate crossflow momentum length scales, all jet trajectories follow a universal relation regardless of the sequential order of jet position and the nund）er of jets. Supported by the velocity and trajectory measurements, the averaged maximum effective crossflow velocity ratio is computed to be in the range of 0.39 to 0.47.

关键词： jet in crossflow multiple jets realizable turbulence model mixing and transport computational fluid dynamics